1. Field of the Invention
The invention relates to a device for cleaning an all-steel sawtooth arrangement of a swift of a card or carding machine with a number of adjacently positioned sawtooth wire sections, wherein between the threads or windings of neighboring sawtooth wire sections a groove of the all-steel sawtooth arrangement is formed extending from the tooth tips of the sawtooth wire sections to the groove bottom, comprising at least one cleaning element for removing foreign particles from the grooves of the all-steel sawtooth arrangement. The invention also relates to a cleaning method that can be performed with such a device.
2. Description of the Related Art
Devices and methods of the aforementioned kind are required, for example, in connection with the operation of a card and, in particular, when operating a carding machine. During the operation of a card, short fibers and neps will collect in the area of a swift arrangement, formed by a sawtooth wire extending in a coil shape about a corresponding support, in the grooves of the all-steel sawtooth arrangement formed between the individual windings of the all-steel sawtooth arrangement. When operating carding machines for processing or producing carded yarns, combed yarns, synthetic fibers, cotton wadding, fleece material etc., foreign particles such as finishes, melted synthetic fiber packets as well as straw, wood, and burs will collect in the area of the corresponding swift or drum arrangements in Morell-type rollers when processing wool. These foreign particles must be removed from the grooves of the all-steel sawtooth arrangement for ensuring a satisfactory work result. For this purpose, it is conventional to employ cleaning brushes which are arranged outside of the actual working area of the swift or drum and rotate about a rotational axis which extends parallel to the rotational axis of the swift. During the cleaning process the cleaning brush bristles sweep through the all-steel sawtooth arrangement and remove foreign particles from the grooves of the all-steel sawtooth arrangement. After leaving the grooves of the all-steel sawtooth arrangements, the foreign particles are then removed conventionally by a suction device or the like from the cleaning brushes so that the cleaning brush bristles will not introduce new foreign particles during the subsequent sweep through the all-steel sawtooth arrangement.
Even though with these known cleaning devices, at least during processing of cotton fibers, satisfactory cleaning results can be obtained, it was found that the cleaning process that can be performed therewith results in additional wear of the all-steel sawtooth arrangement, which is already subjected to great wear due to the fiber processing, this additional wear resulting in a corresponding reduction of the service life of the all-steel sawtooth arrangement. Moreover, when using the known cleaning devices during the operation of a carding machine, only an incomplete cleaning of the corresponding swift or drum arrangement will be obtained. For eliminating the first mentioned deficiency, DE 195 32 592 C1 has already proposed cleaning devices that are useable for the cleaning of circular combs and make a contactless and accordingly wear-reduced cleaning process possible. When using the cleaning devices described in the aforementioned document for cleaning swift arrangements, however, only unsatisfactory cleaning results are obtained, in general. This is true especially for use of the known cleaning devices for cleaning high performance carding machines with which synthetic fibers are processed. In these machines a manual cleaning step must be performed, even when using the known cleaning brushes, in order to achieve a complete cleaning.
It is an object of the present invention to provide a cleaning device of the aforementioned kind with which, while eliminating excessive wear of the all-steel sawtooth arrangement, a satisfactory cleaning can be achieved, even for operating carding machines that are used for processing synthetic fibers, and to provide also a cleaning method to be performed therewith.
In accordance with the present invention, this is achieved with respect to the device in that the cleaning element has a cleaning portion, preferably in the form of a cleaning blade, that can be placed against the groove bottom.
This invention is based on the finding that during the operation of a device for processing textile fibers foreign particles that collect in the area of the all-steel sawtooth arrangement are deposited only to a small degree in the area of the tooth tips of the sawtooth wires and are collected primarily in the area of the groove bottom of the grooves of the all-steel sawtooth arrangement that are formed between the individual sawtooth wire sections of an all-steel sawtooth arrangement. This holds true especially when processing synthetic fibers wherein the foreign particles are substantially comprised of melted products of the synthetic fibers which are produced from the synthetic fibers under the effect of the high temperatures resulting from operation of the high performance carding machines.
These foreign particles can be removed reliably and completely from the all-steel sawtooth arrangement by means of the cleaning portion of the cleaning device according to the invention resting against the groove bottom and being preferably in the form of a cleaning blade comprised of spring steel, without the sawteeth or sawtooth tips used for the actual fiber processing being loaded by the cleaning portion by an appreciable force. Accordingly, a satisfactory cleaning can be achieved with the cleaning device according to the invention, while preventing an appreciable wear of the all-steel sawtooth arrangement, even when melted products resulting during processing of synthetic fibers adhere to the all-steel sawtooth arrangement in the area of the groove bottom. These effects can be achieved in the cleaning of those all-steel sawtooth arrangements in which the groove bottom is formed by the foot of a sawtooth wire that is spirally applied as well as in the cleaning of those all-steel sawtooth arrangements in which the sawtooth wire is applied to a support provided with grooves so that the groove bottom is at least partially formed by the support surface.
In this context, the cleaning device according to the invention can be used not only as an alternative in the cleaning of the swift of a carding machine but also in addition to the known cleaning brushes. A gentle treatment of the all-steel sawtooth arrangement can be achieved in this context in that during the additional use of the device according to the invention cleaning brushes with softer cleaning brush bristles are employed.
In order to achieve an especially good cleaning action, it was found to be expedient to couple the cleaning element with a tensioning device forcing the cleaning portion in the direction toward the groove bottom because a reliable contact of the cleaning portion on the groove bottom is ensured in this way even for irregular surfaces of the groove bottom so that a satisfactory cleaning action can be achieved.
Damage to the all-steel sawtooth arrangement caused by the cleaning process can be reliably prevented when the cleaning portion is secured on a support so as to be movable in a direction counter to the tensioning force produced by the tensioning device. In this manner it is achieved that the cleaning portion can be deflected in a direction counter to the tensioning direction when a high resistance is encountered during the cleaning process, which can be, for example, caused by sawteeth buckled into the grooves of the all-steel sawtooth arrangement, in order to thereby prevent an excessive loading of the all-steel sawtooth arrangement by the cleaning process as well as breaking off of the cleaning portion.
It was found that the last described embodiment of the invention can be realized in a constructively especially simple manner when the cleaning portion is pivotably secured on the support so as to pivot about a pivot axis extending approximately perpendicularly to the tensioning direction. An especially compact design that simultaneously ensures a simple operation can be ensured in this context when the cleaning element comprises a lever supported so as to be pivotable about the pivot axis and extending on both sides of the pivot axis in a direction that extends substantially perpendicularly thereto. The lever is provided on one side of the pivot axis with the cleaning portion and on the other side of the pivot axis with a coupling area for connecting the tensioning device thereto. In this embodiment according to the invention, the tensioning device can be formed in an especially simple way as a spring, preferably in the form of a tension spring, more preferred in the form of a coil spring, secured, on the one hand, on the support and, on the other hand, on the coupling area.
In the case that the cleaning portion meets a resistance in the groove of the all-steel sawtooth arrangement, for example, in the form of a bent sawtooth of the all-steel sawtooth arrangement, and that a deflection movement of the cleaning portion does not occur in the desired way, for example, when the cleaning portion is canted in the groove of the all-steel sawtooth arrangement, it has been proven to be especially expedient for making a continued cleaning process possible when the cleaning device according to the invention has an actuating element with which the cleaning portion can be removed from the groove bottom against the tension of the tensioning device. In this manner it can be achieved that the cleaning process can be continued with manual intervention by means of the actuating element. For this purpose, the actuating element can be configured in a constructively especially simple and very compact manner when it has an eccentric lever that is rotatably secured on the support so as to rotate about a rotational axis extending preferably perpendicularly to the pivot axis and is coupled to the lever of the cleaning element. With such an eccentric lever a disturbance-free removal of the cleaning portion from the bottom of the groove is made possible by a simple rotational movement with which simultaneously a removal force that overcomes even greater clamping forces is transmitted onto the cleaning section by means of the leverage action provided by the eccentric lever.
For cleaning an all-steel sawtooth arrangement of a swift of a carding machine or card formed usually by a sawtooth wire wound in a coil shape onto a circular cylinder mantle surface of a support of the all-steel sawtooth arrangement, it has been proven to be especially expedient when the cleaning portion is forced in the radial direction into the grooves of the all-steel sawtooth arrangement formed between the individual sawtooth wire sections that are defined by the windings of the sawtooth wire and then, during the actual cleaning process, is guided in the axial direction by the all-steel sawtooth arrangement during the course of a rotational movement of the swift, without staggering in the circumferential direction, in order to thus make possible a complete cleaning of the all-steel sawtooth arrangement without requiring the provision of a specific drive element for the cleaning device. For this purpose, the cleaning portion is expediently supported in a slidable manner in a direction transverse to the longitudinal direction of the sawtooth wire section to be cleaned therewith.
This displaceable support of the cleaning portion can be realized constructively in a very simple manner when the cleaning element is secured by a slide which is preferably formed by the support and is slidable along a guide element extending parallel to the displacement direction and formed preferably as an aluminum extruded section.
With such a slide an especially low-friction displacement of the slide, and thus also of the cleaning portion, in the displacement direction can be realized when the slide has at least one guide roller which is supported so as to be rotatable about a roller axis positioned perpendicularly to the displacement direction and can be placed against a guide surface of the guide element, wherein the guide surface is preferably an outer peripheral surface of the guide element.
With the last disclosed all-steel sawtooth arrangement an especially stable and simultaneously low-friction guiding of the slide can be achieved when it has at least two, preferably at least three, more preferred at least four, guide rollers that can be placed respectively against one guide surface of the guide element, wherein the individual guide surfaces are preferably positioned to form an angle of approximately 90xc2x0 with one another. This means that in an especially preferred embodiment of the invention the guide element has a square or rectangular cross-section in a section plane extending perpendicularly to the displacement direction and that at least one guide roller is resting against each one of the outer surfaces of the guide element that form an angle of 90xc2x0 with one another.
By using a slide which is resting by means of guide rollers on the guide element, tilting of the slide, and thus also of the cleaning portion, about a tilting axis extending perpendicularly to the displacement direction can be reliably prevented when the slide has at least two guide rollers spaced apart in the displacement direction and preferably placeable against the same guide surface.
A slide of the cleaning device according to the invention, suitable for coupling a plurality of guide rollers that can be placed against guide surfaces forming an angle of 90xc2x0 with one another, can be realized in a constructively especially simple manner when it comprises an angular profile extending in the displacement direction and having two legs forming an angle of approximately 90xc2x0 with one another. At least one guide roller, supported to rotate about a roller axis that is perpendicular to the leg, is mounted on each leg.
In an especially advantageous embodiment of the invention, the slide is arranged such that it embraces the guide element at least partially. With this all-steel sawtooth arrangement, the guide element can also be used for guiding further processing tools for reconditioning the all-steel sawtooth arrangement, for example, a grinding element, which are received at least partially in the guide element and during the cleaning operation are surrounded by the slide supporting.the cleaning portion. For guiding these further processing tools, the guide element expediently has a guide groove being covered by the slide. If for the operation of the additional processing tools, as, for example, a grinding head disclosed in DE 196 05 635 C2, an additional drive unit is required, an especially compact configuration can be achieved when the guide element is formed as a hollow profile and the guide groove opens into a hollow space penetrating the guide element in the longitudinal direction or the displacement direction, because in this all-steel sawtooth arrangement important components of the drive device, such as, for example, an additional drive belt coupled to the processing tool, can be housed within the hollow space.
As has been explained already above, the cleaning device according to the invention can be operated such that it is not moved in the circumferential direction of the swift of a carding machine or card and that also in the radial direction of the swift only a movement caused by the tensioning device is performed. For this type of operation of the cleaning device according to the invention it is expedient to provide an advancing device that can be secured relative to a frame of a machine, for example, a carding machine, comprising the all-steel sawtooth arrangement. By means of the advancing device the cleaning portion can be advanced in the direction toward the all-steel sawtooth arrangement. Advancing devices useable in connection with this invention are, for example, described in DE 196 05 635 C2. The disclosure of this document with respect to the advancing devices described therein is therefore incorporated into this description by express reference.
The time for cleaning an all-steel sawtooth arrangement by using the cleaning device according to the invention can be significantly shortened when the cleaning device comprises a plurality of cleaning portions spaced from one another in a direction transverse to the longitudinal direction of the sawtooth wire sections. This embodiment of the invention can be used with special advantage for cleaning all-steel sawtooth arrangements which are obtained by a multi-strand winding, as, for example, described according to DIN ISO 5234.
An increased operational reliability in regard to the use of the cleaning device according to the invention can be obtained when the cleaning portion is not only movable in a direction opposite to the tensioning force of the tensioning device but is additionally produced of an elastically deformable material. Accordingly, pursuant to an especially preferred embodiment of the invention, at least one of the cleaning portions is manufactured of spring steel.
As can be taken from the above description, a method according to the invention for cleaning an all-steel sawtooth arrangement by using the cleaning device according to the invention is characterized primarily in that a cleaning portion of the cleaning device is introduced into a groove of the all-steel sawtooth arrangement formed between neighboring sawtooth wire sections of the all-steel sawtooth arrangement and brought into contact with the groove bottom, wherein subsequently a relative movement between the all-steel sawtooth arrangement and the cleaning portion is initiated in order to so lift foreign particles off the groove bottom and remove them from the all-steel sawtooth arrangement. In this context, the relative movement between the cleaning portion and the all-steel sawtooth arrangement during the cleaning of an all-steel sawtooth arrangement, mounted on the swift of a carding machine or a card in a circumferential coil shape, is realized expediently in that the swift is set in motion rotatingly while the cleaning portion is stationary in the circumferential direction and is guided in the axial direction of the swift by the coil-shaped rotating sawtooth wire.
In the following, the invention will be explained with reference to the drawing to which reference is being had with respect to all details that are important to the invention but not explained in detail in the description.